I have been using SolidWorks for about 2weeksandhave a question about constraining sketched. I find that Solidworks is very forgiving when it comes toleaving sketches under constrained. I would say that in all the parts that I have created, most of the sketches are under defined.I have found that this has some unexpected results when I try to edit the features. Lengths that were assumed equal are no longer equal after a dimension edit, lines are no longer colinear, etc.
My question to the expert users: Do you fully constrain each and every sketch?
I have gone back and constrained all my sketches but for SolidWorks to allow the creation of under defined features seem like a invitation for desaster.
01-07-2008, 06:30 PM
I fully constrain every single sketch for the very reason you describe- the response to changes is unpredictable in unconstrained sketches.
Go to Tools > Options > System Options tab and put a check next to "Use fully defined sketches." This makes it so you cannot exit the sketch before constraining the system.
However:I leave it off, because sometimes I temporarily leave a sketch unconstrained for whatever reason. But it is good practice to always fully constrain your sketch for the finished product.
01-08-2008, 04:21 PM
I agree mostly with SSLaser and it is good to start with "Use fully defined sketches" turned on, but as you improve your design skills you will find that some sketch segments need only constraints between them and not the whole part. As you work with Solidworks, you will see what I mean.
01-09-2008, 02:13 AM
Yes. SSLaser and MMEXIA has right. But, if you want to use IN CONTEXT sketch you can not define FULLY those sketches. For example, a simple assembly:abox with six walls. If you fully define the sketches for walls you have ONE box. Of course, you can use configurations for other boxes, but I prefear other method: I define 3 newplanes (DEEP ,LEVEL, BREADTH)paralel with thepredefineted planes (FRONT, TOP, RIGHT) and I mate the walls of the box at this six planes. Now, for all wals I have2 sides ofeach sketch fixed (because the mate).After that I define the other 2 sides of each sketch IN CONTEXT (paralel or coliniar or...with the apropiate wall). In this case if I modify the distances forDEEP or LEVEL or BREADTH plane (or for all) I have a new box. So I have no need to manage more and more configurations, one for each box. Hope you unterstand. If not, hear is my eMail adress: ALT.MIHAI@YAHOO.COM (and the MESSENGER too).